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Guv Bob Guv Bob is offline
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Default RC Circuit for On Delay Timer

"Jim Mueller" wrote in message b.com...
On Fri, 06 Sep 2013 09:57:57 -0700, Guv Bob wrote:

snip


Thanks Jim. I have no experience with 555 timers. Where would I find a
basic circuit for this application using a 555?


Here's a data sheet: http://www.ti.com/lit/ds/symlink/lm555.pdf. It has
a number of generic circuits. What you want is a monostable circuit. It
can be set up to trigger from power-on or from a separate signal. Can
you modify the example circuit yourself or do you need help?

--
Jim Mueller

To get my real email address, replace wrongname with dadoheadman.
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Thanks, Jim, that's a big help. I'm afraid I do need more help. Someone also mentioned needing a diode. I'm pretty lost at the component level.

If it helps, the application is to energize a small LED for approx 5 seconds when 12VDC is applied to the input. After 5 seconds the LED should go off even though 12VDC is still on the input.

I don't have the LED current draw, but it's very small - probably on the order of 10ma.

Many thanks for this help!

Bob